Angle iron or oak?

[dadiOH]

I recently made a sheet goods storage thing. It is 4' high x 8' long x 2' wide and is divided lengthwise into two 1' wide sections.

The center divider is a full sheet of 4x8x3/4 ply; the outboard sides are the same thing but with the ply ripped diagonally. Each of those have vertical 2x3s screwed and glued along the bottoms of the ply. The bottoms of each 12" compartment are 3/4 ply glued and screwed to the top edge of the

2x3s to hold the two sections together. There is also a 3/4 ply back attached to the vertical pieces of ply but not to the bottoms. Front is open (naturally :) The whole works is on casters.

I figured the bottom would deflect some once I loaded it but not as much as it does. The center across the 24" dimension is close to 1/2" lower than the outboard edges. The deflection is more than enough to deflect the center vertical axis of the casters so the thing won't roll.

Obviously, I need to beef up the bottom in the 24" direction, i.e., across the width. The question is, with what?

I've considered three things: 1. 2-4 pieces of 5/4 white oak maybe 6" wide 2. 2-4 pieces of white oak about 2 1/2" wide but on edge 3. 2-4 pieces of angle iron.

I'd love some input. If you say "iron", what size would you suggest and would it be better attached in an inverted "L" or "V" position?

[Swingman]

"dadiOH" wrote

The above, only use scrap plywood ... should ultimately be stiffer than cross grain wood.

Try it ... if it doesn't do the trick, go for angle iron or square tubing.

[mkaras]

You could consider also consider trussing it with a steel rod that is threaded on each end much the way that step ladder threads are strengthened.

- mkaras

[Doug Houseman]

The easy thing would be to put a couple more casters in the center...Probably one in the middle of the cart and one at each end.

This will solve the bow in the middle problem and take some weight off the existing casters. Make sure you get some the swivel easily - so as you tow the cart around the middle casters don;t lock up.

[Phisherman]

The angle iron seems to be the best/easiest solution, although probably not the cheapest. Drill holes every 4" along one edge and fasten in the "L" position with wood screws.

I like using a lip around the bottom edge of shelves to stop deflection. For example, I use a 1.5" x3/4" white oak piece, rabbet a corner, glue, drive finish nails or clamp and allow to cure overnight. You will have to take off a little of the shelf to allow space for the lip. A lip on the back side will add more strength to resist bending. Of course this method can work better during the construction phase.

[Phisherman]

I like this solution!

[dadiOH]

Thank you all for your thoughts. I'll probably add a couple of casters on the center line. If I were starting anew, I'd probably try the steel rod truss idea...the physics of it appeals to me :)